The present invention relates to a composition containing a chelating agent, more particularly to an EDTA complex to be administered in suppository form.
Chelating agents are well known organic compounds that are capable of forming complexes of multivalent metal ions. Chelation therapy, involving the administration of EDTA (ethylene diamine tetraacetic acid) complexes for removing arterial calcium plaque, or for removing heavy metals such as lead has been extensively employed. For example, EDTA has been used to remove high levels of lead from the bloodstream of those who have been exposed to lead paint. Intravenous injection of chelators has been widely used for the treatment of atherosclerosis. Intravenous administration may take several hours per session, and several sessions per month for many months. Such a treatment schedule is inconvenient to the patient and health care provider.
Oral chelation therapy is also well known as a more convenient method. However, when administered orally, a very low percentage of the EDTA complex is actually absorbed by the bloodstream.
It is known that EDTA may be administered in a suppository form. Bennett U.S. Pat. No. 5,602,180 relates to a method of administering a disodium EDTA complex in the form of a controlled release suppository. U.S. Pat. No. 5,602,180 is hereby incorporated into this specification by reference.
Disodium EDTA has the disadvantage of raising sodium levels. Sodium stimulates the sympathetic system, causing, among other effects, an increase in blood pressure, pulse pressure, and heart rate. These affects are undesirable in the patient suffering from atherosclerosis, a condition for which EDTA therapy is often prescribed. As sodium increases pulse pressure, the amplitude of the cyclic changes in lumen size and shape are increased. These cyclic changes may lead to the disruption of plaque and subsequent myocardial infarction. See Valentin Fuster, MD, xe2x80x9cThe Vulnerable Atherosclerotic Plaquexe2x80x9d (American Heart Association).
The present invention provides an alternative to the intravenous injection or oral formulation of EDTA chelating agents. A method of administering EDTA complexes includes forming a suppository containing a magnesium di-potassium EDTA complex. The suppository may also contain a controlled-release agent, which, when used, will release the complex over a period of several hours.